Thomas fairley



No. 623,892. Patented Apr. 25, I899. T. FAIBLEY.

EXTRAGTOB.

(Application filed Dem 29, 1897.)

(No Model.)

Allarney I UNITED STAT S PATENT OFFICE.

THOMAS FAIRLEY, OF LEEDS, ENGLAND.

EXTRACTOR.

SPECIFICATION forming part of Letters Patent No. 623,892, dated April 25, 1899.

Application filed December 29, 1897. Serial No. 664,177. (No model.)

T0 all whom it may concern:

Be it known that I, THOMAS FAIRLEY, a subject of the Queen of England, residing at Leeds, England, have invented a certain new and useful Extractor, (for which I have obtained Letters Patent in Great Britain under No. 1,666, dated January 23, 1896; in Germany under No. 94,850, dated December 4, 1896; in France under N0. 262,850,dated January 6, 1897, and in Belgium underNo. 125,633, dated January 9, 1897,) of which the following is a specification.

Screw conveyers working in troughs, tubes, or cylinders are used for conveying wet or dry materials in various manufacturing operations. By their means a solid material more or less finely divided can be carried upward or forward through a tube or cylinder against a fiow of washing liquid or solvent passing in the opposite direction. With a supply of power to rotate the shaft of the screw conveyer and proper adjustment of the liquid entering and leaving the apparatus a continuous extractor may be thus obtained.

My invention relates to a special form of screw conveyer adapted to be advantageously used in apparatus for the manufacture and purification of certain salts, for instance. Such apparatus is also well adapted for the extraction or separation of many substances from mixtures by means of water, alcohol, or other liquid solvents.

My invention is illustrated in the accompanying drawings, in which- Figure 1 is a longitudinal section of the extractor. Fig. 2 is a cross-section on lines 2 2 of Fig. 1. Fig. 3 is a cross-section on lines 3 3 of Fig. 1.

My extractor consists, essentially, of a divided screw and an inclosing casing B. The screw instead of being made in a single piece is here shown as made of two separate and distinct parts, the shaft A being divided longitudinally into two parts, each of which has a portion of the wings A secured thereto. The casing B is shown provided with a jacket B, surrounding it from end to end for the purpose of applying heat or cold externally. Connected with the casing at or near its up- I per end is an inlet-pipe C for the admission of the solvent. At the opposite lower end of the casing, upon its upper side, is a tube D, which serves as a discharge for the saturated solvent. Also connected with the casing at any suitable point upon its upper side between the two pipes D and O is a pipe E, through which the solid substance is introduced into the casing, and at the upper end of the casing upon its lower side is a pipe F, through which the solid substance is discharged.

The improved form of screw apparatus may be described as in its simplest form derived from an ordinary screw conveyer by dividing it along a section passing lengthwise through the axis of the shaft of the screw into two equal and similar'parts. If now the free ends of the divided shaft be fitted with sleeves S passing over them, the two parts of the shaft can slide upon each other and be retained in any desired position by simple mechanism. Thus the threads of the screw on one half may precede or follow those on the other half by any regulated distance, which need not exceed half the interval between two adjacent threads of the screw. In this position the divided screw conveyer may be made to rotate as one whole just as an undivided screw would do.

So long as the halves of the screw fit together when set exactly opposite they may be mounted on twin shafts working in sleeves of suitable form, so that the halves of the screw can be fixed at regulated distances.

The same method can be applied in the division of a screw conveyer into more than two parts. When such a divided screw is mounted inside a tube or cylinder which it fits accurately, it forms on rotating it at a regulated speed the working part of a very efficient apnearly-spent material is completely washed or extracted by meeting with fresh solvent, while the nearly-satu rated solvent meets with The solid substance is pushed up-.v

fresh solid substance, so that before leaving the apparatus it may be completely saturated. An extractor provided with a divided screw, as above, has the following advantages:

The washing liquid or solvent can get with equal facility to all parts of the cylinder containing materialnear the center as well as n ear the circumference and edge of the screw. The rotation of the divided screw secures very perfect mixing of the materials, as the edges of the divided screw cut into the materials in different parts at each revolution. 1

The rotation also tends to break up any agglutinations or clogging of the solid materials.

In working the solid materials to be extracted are fed into the bottom or lower end of the apparatus through tube E and are then carried forward or upward by the action of the rotating screw conveyer and at the same time thoroughly mixed by the action of the divided screw. Finally, the spent material issues from the top or upper part of the cylinder through tube F, after which it. may be pressed, dried, or treated as may be desired.

The washing liquid or solvent enters the cylinder of the extractor apparatus at or near the upper end through tube 0 and passes downward over and through the divided screw and leaves the extractor at the bottom end through tube D, charged with the substance or substances which it is required to dissolve.

In the preparation of salts the solid material issuing from the upper end is frequently the chief object of the operation-as, for example, in the purification of a mixture of ammonium nitrate containing some sodium nitrate.

The apparatus may be jacketed so as to apply either heat or cold externally, according to the work required. Thus the apparatus may be used both in the solution of solids in hot liquids and in the separation of solids as they crystallize out from hot liquids passing through an apparatus externally cooled. In this latter case it may be convenient to supply the liquid toward the lower end of the apparatus.

If necessary, during the working of the apparatus the relative positions of the parts of the screw may be altered continuously or intermittently, the whole length of one or both parts of the screw being raked backward and forward, as may be desired. This affords a further means of guarding against possible clogging and of varying the working of the apparatus.

Various means may be employed to adjust or alter the position of the parts of the screw, such as a toothed rack on one or both the halves engaging with a toothed wheel or pinion. The following gives a firm and accurate adjustment which can be varied without stopping the working. The divided axis can be made hollow, so as to inclosc a smaller rod screwed and fitting into screwed parts projecting on the inner side of one of the halves of the divided axis. This central rod is held by bearings from the inner side of the other half of the axis, and it projects outside beyond the axis, so that it can be turned and shifted.

The rate at which the solid materials are pushed forward depends on the pitch and rate of rotation of the screw. Vithin practicable limits a slower rate of rotation permits shorter cylinders to be used, still securing complete saturation of the solvent employed. The adjustment for this purpose must depend on the nature of the materials.

The rate at which the liquids pass through the cylinder depends on, first, the fineness or character of the materials; second, 011 the accuracy of fitting of the screw inside the cylinder and the degree to which the parts of the divided screw are separated, and, third, on the vertical height of the fall of the liquid in the cylinder. This fall may be varied according as the apparatus is set upright or in an inclined position. In general with these adjustments one cylinder may be found suffieient for complete extractions, but several cylinders may be used in series, using right or left handed screws, as may be necessary.

Having thus described my invention, 1 claim therein as new and desire to secure by Letters Patent-- 1. An extractor for treating solids with solvents composed of a divided conveying-screw, a longitudinally-divided shaft on which the screw is mounted, a casing inclosin g said conveying-screw and being provided with two inlets and two outlets, means for rotating the screw and means for adjusting and setting the divided shaft and screw, substantially as described.

2. An extractor for treating solids with solvents composed of a divided conveying-screw, a longitudinally-divided shaft on which the screw is mounted, a casin g inclosing said conveying-screw and being provided with two inlets and two outlets, a jacket surrounding the casing, means for rotating the screw and means for adjusting and setting the divided shaft and screw, substantially as described.

3. An extractor for treating solids with solvents composed of a divided conveying-screw, a longitudinally-divided shaft on which the screw is mounted, a casing inclosing said conveying-screw and being provided with two inlets and two outlets, means for rotating the screw, and a device for altering and adjustin g the position of the wings of the screw consisting of a small rod with adjusting-wheel attached and screwed into threaded parts inside of one half of the divided shaft and held by bearings on the other half of the shaft, substantially as described.

4. In an extractor, an inclosing casing, and a divided screw placed therein, combined with means for revolving the screw, and means for adjustingaportion of the screwendwisewithdivided shaft and held by bearings on the in the casing, substantially as shown. other half of the shaft, substantially as de- 5. In an extractor for treating solids with scribed. solvents an adjustable .screw eonveyer coln- In testimony whereof I have hereto set my 5 posed of a divided screw and longitudinallyhand in the presence of the two subscribing 15 divided adjustable shaft of which each half Witnesses.

carries one set of the endwise-movable screw- THOMAS FAIRLEY. wings and an inclosing casing, a rod with ad- WVitnesses: justing-wheel attached thereto and screwed BENJAMIN ARTHUR BURRELL,

[0 into threaded parts inside of one half of the JOHN HENRY SUGDEN. 

